Global ETD Search

11	Responses of Ground-dwelling Invertebrate Communities to Disturbance in Forest Ecosystems Perry, Kayla I. January 2016 (has links) No description available. Ecology Entomology forest floor invertebrates disturbance canopy gap woody debris dispersal ground beetles Carabidae emerald ash borer
12	Survival and growth of planted seedlings on woody and non-woody forest floor substrates in high and low light environments of coastal British Columbia Klinka, Karel January 2001 (has links) In the wetter climates associated with the coastal forests of northwestern North America, coarse woody debris (CWD) accumulations in the form of snags, downed boles, and large branches can be large in natural forest ecosystems. Seedlings often regenerate on stumps and downed logs in the understory of old-growth coastal forests. The question remains though, whether CWD is a necessary component for seedling survival and growth in forests managed for commodity production. This study addresses one concern of forest managers: is there an immediate nutritional or moisture supply advantage conferred by CWD for the survival and growth of seedlings in the coastal climate of British Columbia? We compared survival and growth of seedlings planted in decaying wood compared to non-woody humus forms and mineral soil under heavy shade and full light conditions. Low light environments are of particular interest since reports of the strong association between CWD and regeneration has primarily referred to understory seedlings and saplings in old-growth forests. Seedling survival Coarse woody debris Coastal British Columbia Douglas-fir Forest floor Light conditions Pacific silver fir Soil nutrients Western hemlock Western redcedar
13	Forest floor dynamics across a chronosequence in the coastal western hemlock zone Klinka, Karel January 1997 (has links) The forest floor represents the uppermost organic and organicenriched mineral soil horizons. They have been formed by the deposition of organic material and the subsequent biologically mediated decomposition. The forest floor influences rooting-zone temperature, aeration, moisture, and nutrient conditions, and hence, forest productivity. Considering the importance of the forest floor, and the fact that it is exposed to disturbance (being the surface layer), we need to assess the potential impacts our logging practices may have. Clearcutting, one of the contentious silvicultural practices used in British Columbia, is imputed to most adversely affect ecosystems and sustainability. We assessed the long-term impact of clearcutting on the forest floor by documenting changes in the thickness, chemical and biotic properties of the humus form across a chronosequence of forest stands. The study was located in the largest and most representative portion of the coastal rainforest the Very Wet Maritime Coastal Western Hemlock (CWHvm) subzone. Clearcutting West Coast hemlock Biodiversity Forest floor Humification Humus Soil fauna Plant succession Forest biodiversity Soil chronosequences Soil nutrients Soil microbiology
14	The association between western hemlock fine roots and woody versus non-woody forest floor substrates in coastal British Columbia Klinka, Karel January 2001 (has links) In the wetter climates associated with the coastal forests of the Pacific Northwest, coarse woody debris (CWD) accumulations in the form of snags, downed boles, and large branches can be large in natural forest ecosystems. Although maintaining organic matter for sustainable site productivity is not in dispute, the importance of CWD as a source of soil organic matter is questionable. Forest managers attempting to optimize timber production need to know how CWD affects short-term forest tree growth and productivity. This study addresses the question of the immediate value of CWD for growth of mature (90 year old) western hemlock (Hw). Because of practical difficulty with mature trees growing in different substrates, we utilized fine root distribution or proliferation, as an indicator of important substrates. Coarse woody debris West coast hemlock Western hemlock Forest floor Humification Humus forms Soil nutrients Site quality Root biomass Root density Root formation Substrates, Plant
15	Structure and regeneration of old-growth stands in the engelmann spruce - subalpine fir zone Klinka, Karel January 1998 (has links) Old-growth stands are important for management, conservation, wildlife, recreation, and maintaining biological diversity in forested landscapes. However, we are lacking the information needed to adequately identify and characterize old-growth stands. This is especially true for high elevation, interior forests. The characterization of stand structure and regeneration pattern will help in the development of site-specific guidelines for identifying old growth stands and restoring some of the old-growth characteristics in managed stands. This pamphlet presents a synopsis of a study investigating stand structure and regeneration of old-growth stands in the Moist Cold Engelmann Spruce - Subalpine Fir (ESSFmc) Subzone near Smithers, B.C. The three stands selected for the study were located on zonal sites, each in different watersheds, and the stands were established after fire. The criteria used for selection were: i) absence of lodgepole pine, ii) presence of advanced regeneration, and iii) abundant snags and coarse woody debris. These stands were presumed to represent the old-growth stage of stand development or the final (climax) stage of secondary succession. Age Diameter Height Engelmann spruce Engelmann spruce - subalpine fir Forest floor Coarse woody debris Old growth forest ecology Forest regeneration Snowmelt Stand structure Subalpine fir Abies lasiocarpa Fire ecology Understory plants Moist cold subzone
16	Forest floor nutrient properties in single- and mixed-species stands of Western hemlock and Western redcedar Klinka, Karel, Collins, D. Bradley, Montigny, Louise E. M. de, Feller, M. C. (Michael Charles), Chourmouzis, Christine January 2001 (has links) The influence of tree species on forest soils has been the subject of study for at least a century. Of particular interest have been western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western redcedar (Thuja plicata Donn ex D. Don) – two of the most common tree species in coastal and southern British Columbia, but each with a different nutrient amplitude. It has generally been found that acid, mycogeneous Mor humus forms develop in hemlock stands, while less acid and more zoogenous Mormoder, Moder, or even Mull humus forms develop in redcedar stands. The objective of this study was to determine the influence of hemlock and redcedar, growing separately and together, on forest floor nutrient properties. The questions addressed were: (1) does each stand type have unique forest floor nutrient properties? and (2) can any forest floor nutrient property discriminate between stand types? Forest floor Humus form Mixed-species stands Nutrient properties Single-species stands Site quality Soil acidity Soil nutrients West coast hemlock Western hemlock Western redcedar Carbon - nitrogen ratio Calcium concentration
17	Factors Affecting Gaseous Mercury (Hg) Emissions from Soils: Insights from Disturbance due to Frest Harvesting and Hg Source Depth Manipulation Mazur, Maxwell 05 December 2013 (has links) This thesis explored the impacts of forest harvesting on gaseous elemental mercury emissions from forest soils in both field and laboratory studies, through novel use of enriched mercury isotope tracers. Forest floor Hg emissions, sourced from legacy deposition, increased proportionally to the vegetation quantity removed, with biomass harvesting most exacerbating emissions. Contemporary Hg deposition did not appear to be influenced by harvesting. Some of the tracer was rapidly lost to the atmosphere (~8%), but most was sequestered within the soil. Two regimes facilitating Hg emissions were observed in low-light conditions. Under extremely dry conditions deeper Hg sources (> 2cm depth) were as equally susceptible to emission as shallower sources. Following wetting to field capacity, emissions were elevated only from shallow sources, likely as a result of upward capillary transport. Impacts of vegetation removal and dry fluxes are previously uncharacterized and may constitute large additional sources to regional atmospheric Hg cycling. Mercury Emission Forest Harvesting Soil Isotope Source Depth Dry Flux Soil Wetting Flux Wet Flux Solar Radiation Soil Moisture Leaf Litter Sequestration ICP-MS Tekran Tracer Enriched Mercury Isotope Forest Floor Deposition Biomass Harvesting Capillary Transport Hg Cycling 0368
18	Factors Affecting Gaseous Mercury (Hg) Emissions from Soils: Insights from Disturbance due to Frest Harvesting and Hg Source Depth Manipulation Mazur, Maxwell 05 December 2013 (has links) This thesis explored the impacts of forest harvesting on gaseous elemental mercury emissions from forest soils in both field and laboratory studies, through novel use of enriched mercury isotope tracers. Forest floor Hg emissions, sourced from legacy deposition, increased proportionally to the vegetation quantity removed, with biomass harvesting most exacerbating emissions. Contemporary Hg deposition did not appear to be influenced by harvesting. Some of the tracer was rapidly lost to the atmosphere (~8%), but most was sequestered within the soil. Two regimes facilitating Hg emissions were observed in low-light conditions. Under extremely dry conditions deeper Hg sources (> 2cm depth) were as equally susceptible to emission as shallower sources. Following wetting to field capacity, emissions were elevated only from shallow sources, likely as a result of upward capillary transport. Impacts of vegetation removal and dry fluxes are previously uncharacterized and may constitute large additional sources to regional atmospheric Hg cycling. Mercury Emission Forest Harvesting Soil Isotope Source Depth Dry Flux Soil Wetting Flux Wet Flux Solar Radiation Soil Moisture Leaf Litter Sequestration ICP-MS Tekran Tracer Enriched Mercury Isotope Forest Floor Deposition Biomass Harvesting Capillary Transport Hg Cycling 0368
19	Ecology and Conservation Biology of the North American Wood Turtle (Glyptemys insculpta) in the Central Appalachians Krichbaum, Steven P. 28 June 2018 (has links) No description available. Animals Ecology Environmental Science Forestry Zoology Wildlife Management Wildlife Conservation habitat selection turtle population biology program MARK forest temperatures turtle temperatures forest floor humidity forest herbaceous flora tree importance values
20	Mechanisms of Carbon and Nitrogen transformations in Forest floors of Beech-, Spruce- and Mixed Beech-Spruce Stands / Mechanismen der Kohlenstoff- und Stickstoffumsetzungen in der Humusauflage der Buche-, Fichte- und Buchen-Fichten-Mischbeständen Bagherzadeh Chaharjouee, Ali 16 February 2004 (has links) No description available. Forest Sciences and Forest Ecology Humusauflage Fichte Buche CO2 N2O C mineralisation N mineralization Nährstoff Q10 microbielle biomasse Sämlinge 15N Nitrat Ammonium retention 630 Landwirtschaft Veterinärmedizin forest floor spruce beech CO2 N2O C mineralization N mineralization nutrient Q10 microbial biomass seedling 15N nitrate ammonium retention recovery 48.32 YPA 000: Forstliche Bodenkunde

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